398 ENTOMOLOGICAL NEWS [NoV., 'l2 



terial was taken from the large branches where the insect can 

 reach its maximum growth, whereas Mr. Cockerell's material 

 comes from the small terminal shoots. 



As might be expected, a study of the antennae of the two 

 failed to present any salient characters, and as an evidence of 

 the inconstancy of such measurements the following formulae 

 are submitted : 



Eriococcus artemisiae Kuwana. Co-type material on Arte- 

 misia sp. at foot-hills of Sierra Morena, Stanford University, 

 Cal. S. I. Kuwana, Collector, March 24, 1900. [7, i, 6, 4 (3. 



2), 5] ; [7, 1 (5. 2) (6, 4. 3)] ; [7- 1, 2, 4 (6, 2) 5]. 



Erium lichtensioides Ckll. Type material on Artemisia fri- 

 gida, Fort Collins, Col. C. P. Gillette, Collector, September 

 25, 1896. [7, I (2, 6), 4 (5, 3)] ; [7, I, 4 (2, 6), 3, 5]. 



Erium lichtensioides Ckll. on Artemisia tridentata from Tol- 

 land, Col. T. D. A. Cockerell, letter. February 13, 1912. [7, 

 I, 2, 3 (4, 6) 5] ; [7, I, 2 (3, 6) 5, 4] ; [7, i (2, 5) (3, 4) 6]. 



A careful study of the above formulae and many not in- 

 cluded in this paper is conclusive evidence, to the writer, that 

 measurements of antennal joints afford a very weak and vari- 

 able character since in not a single instance do the lengths 

 agree throughout even when the measurements are made of 

 antennae of the same individual. There is also another feature 

 worthy of notice, viz., the presence of seven- and eight- 

 jointed antennae. This occurs in the material collected by 

 Mr. Timberlake, although the division between four and five 

 is not so prominent. A study of the legs failed to present any 

 substantial characters to warrant a separation. 



In conclusion, it is the belief of the writer that artemisiae 

 is founded on unstable grounds, since the co-type material does 

 not exhibit any character which would warrant its retention 

 as a valid species. It surely does not belong to the genus 

 Eriococcus as it is now defined owing to the presence of only 

 six hairs around the anal ring, a character belonging to the 

 genus Erium. Occurring as they both do on Artemisia and 

 possessing no features worthy of separation, it is therefore 

 proposed that Eriococcus artemisiae Kuwana be reduced to a 

 synonym of Erium lichtensioides Cockerell. 



